A Portable Fast Neutron Monitor for Determining Uranium Deposit Weights in Closed Equipment

Diffusion Plant for the measurement of the weights of deposits of uranium fluoride compounds in process equipment. With this method, the neutron radiation resulting from the collision between uranium alpha particles and fluorine atoms is measured. Depending upon the geometry of the deposit, weight estimates accurate to ten percent have been obtained. The Neutron Monitor, shown on slide 1, was developed as part of this work and is a portable fast neutron detector consisting of a 22 lb. probe, a l4 lb. battery powered sealer, and a 35 foot interconnecting cable. The sealer incorporates an adjustable preset timer, and both a decade and a mechanical counter for registering the total count. It will operate for about 11 hours before recharging of the nickel-cadmium batteries is necessary. Solid deposits of uranium compounds form in processing equipment containing gaseous uranium hexafluoride when moist air in leakage occurs, when process equipment becomes overheated, or when it is cooled below the condensation temperature. Nuclear safely considerations dictate that such deposits be located and the cause removed before a hazardous quantity can accumulate. In addition, knowledge of the weights of such deposits is desirable for inventory control purposes.